The technology relates to an engine control apparatus that cleans a deposit generated in an intake system.
A deposit lay on an intake port or an intake valve of an engine. The deposit is carbide or oxide of, for example, fuel or engine oil. Because the deposit laid in a large amount on, for example, the intake port may influence an operation state of the engine, pursuits have been made for removal of the deposit from the intake system. For example, Japanese Unexamined Patent Application Publication (JP-A) No. 2001-289097 has made a proposal for a control apparatus that flows back fuel from a combustion chamber to an intake port, by changing injection timing of the fuel in units of predetermined travel distances. The control apparatus described in JP-A No. 2001-289097 positively attaches the fuel to the intake system, allowing the fuel to clean the deposit on the intake system.